{Momofuku Banana Hazelnut Cake}
Serves:: 1 16cm diameter cake
Banana sponge cake:
  • 85g butter, softened
  • 200g white sugar
  • 50g egg
  • 110g buttermilk
  • 20g vegetable oil
  • 225g banana slices
  • 225g all-purpose flour
  • 3g baking powder
  • 3g baking soda
  • 2g salt
Hazelnut ganache:
  • 60g heavy cream
  • 10g milk
  • 60g milk chocolate
  • 85g hazelnut paste
  • 50g fudge sauce (recipe follows)
  • 1g salt
Fudge sauce:
  • 30g dark chocolate 70%
  • 15g cocoa powder
  • 100g glucose syrup
  • 20g white sugar
  • 60g heavy cream
Hazelnut crunch:
  • 100g hazelnut paste
  • 80g hazelnut brittle (recipe follows)
  • 80g paillete feuilletine
  • 15g dark chocolate 50-60%
  • 0.5g salt
Hazelnut brittle:
  • 100g white sugar
  • 60g hazelnuts, roasted
Banana diplomat cream:
  • 225g banana
  • 75g heavy cream
  • 85g milk
  • 80g white sugar
  • 25g cornstarch
  • 2g salt
  • 60g egg yolk
  • 5g gelatin + 30g water
  • 165g heavy cream, whipped
Hazelnut frosting:
  • 25g butter, softened
  • 65g hazelnut paste
  • 20g powdered sugar
  • 0.5g salt
Banana sponge cake:
  1. Sift the flour, baking powder, baking soda and salt.
  2. Mix the butter and sugar in the bowl of your mixer until light and pale.
  3. Add the egg and mix at least 5 minutes. Stream in slowly the oil, followed by the buttermilk. Don't add too much at once as it will cause the emulsion to break. It is crucial to keep the mix as smooth and emulsified as possible. Whip the mixture for 8 minutes on medium to high speed until double in volume.
  4. Add the banana slices and mix just until they break into smaller pieces.
  5. Add the dry ingredients and mix on low speed just until combined.
  6. Spread the batter in a 30x25cm tray and bake in the preheated oven at 170C for 15-20 minutes.
  7. Cool down then cut 3 discs of 16cm diameter. Usually the third disc needs to be built up from the leftovers, but that is ok, it will hold up. Keep aside.
Hazelnut ganache:
  1. Combine the cream and milk and warm up.
  2. Melt the chocolate.
  3. Pour the hot liquid over the chocolate and mix with a blender, adding the hazelnut paste and fudge sauce, as well as salt while blending.
  4. Cover with foil and place aside.
Fudge sauce:
  1. Combine the glucose, sugar and cream in a pot and warm up.
  2. Pour over the chocolate and cocoa powder and mix to combine.
  3. Scale what you need and keep covered in a bowl.
Hazelnut crunch:
  1. Melt the chocolate and mix it with the rest of the ingredients.
  2. Keep aside.
Hazelnut brittle:
  1. Caramelize the sugar until golden brown.
  2. Mix it with the hazelnuts then transfer on a tray lined with baking paper.
  3. Cool down then break into small pieces in a kitchen machine.
  4. Scale what you need and keep aside.
Banana diplomat cream:
  1. Bloom the gelatin in water.
  2. Mix the egg yolk with salt and sugar, then add the cornstarch and mix well.
  3. Blend the banana with the cream and milk then mix with the egg yolk and starch.
  4. Transfer in a small pot and cook until the cream is stiff and shiny. It takes around 1 minute from the moment it starts to boil.
  5. Remove from heat and add the gelatin.
  6. Cool down in the fridge covered with foil.
  7. Whip the heavy cream.
  8. Mix the chilled banana cream in the bowl of your mixer until smooth and creamy again. Fold in the whipped heavy cream.
Hazelnut frosting:
  1. Mix all the ingredients together in a bowl.
  2. Keep the frosting aside until needed.
To assemble the cake:
  1. Arrange all your cake components on your working table - it will be much easier to assemble the cake with everything on sight.
  2. Line a 16cm cake ring with acetate sheets.
  3. Place a layer of banana sponge on the bottom of the ring - usually this first layer is the one that you made out of leftovers. Press it slightly then brush it with milk.
  4. Spoon half of the hazelnut ganache, followed by ⅓ of the hazelnut crunch.
  5. Next layer is ½ of the banana cream, followed by another banana sponge, milk soak, the other half of ganache, ⅓ of crunch, the other half of banana diplomat and the final layer of banana sponge.
  6. Bruch the final sponge with milk then cover with the hazelnut frosting.
  7. Decorate with the ⅓ of crunch you have left from assembling the layers.
  8. Refrigerate for at least 8 hours.
  9. Enjoy!
Recipe by Pastry Workshop at https://pastry-workshop.com/momofuku-banana-hazelnut-cake-tort-cu-alune-de-padure-si-banane/